Statistics And Probability Question 191
Question: A bag contains 3 red, 7 white and 4 black balls. If three balls are drawn from the bag, then the probability that all of them are of the same colour is
Options:
A) $ \frac{6}{71} $
B) $ \frac{7}{81} $
C) $ \frac{10}{91} $
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
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Required probability $ =\frac{{}^{3}C_3+{}^{7}C_3+{}^{4}C_3}{{}^{14}C_3} $ $ =\frac{1+35+4}{14\,.\,13\,.\,2}=\frac{40}{14\,.\,26}=\frac{10}{91}. $
BETA
